Sir David, the former chief executive of Network Rail, was brought in to rescue the controversial project after his successful stewardship of the Olympic Delivery Authority.

His contract was extended only in January this year after he was initially appointed for a two-year term beginning in January 2014.

In November of that year, Sir David told MPs on the transport select committee that he would “wait to see what progress we have made” before seeking a long-term extension.

Joe Rukin, campaign director of Stop HS2, said that Sir David’s departure so soon after his contract was extended would be “a terrible vote of no confidence in HS2 from the man who was supposed to save it”.

Only nine weeks ago, Sir David made a bullish speech in Manchester claiming that HS2 was “already changing Britain” and “people are much clearer about why HS2 is in Britain’s long-term national interest”.

Safety experts warn the track could break up and trains derail at the very high speeds proposed, the highest of any service in the world using conventional track.

The government spending watchdog, the National Audit Office, which has long been sceptical of HS2’s value for money, is conducting a further review of the project. A Cabinet Office review is also under way.

In a report last month, MPs on the public administration select committee savaged HS2’s communication with residents affected by the project, leading to a perception that it “has disregard for the public.”

An independent review commissioned by the Government and a parliamentary ombudsman report came to similar conclusions.

The £55.7 billion scheme has faced repeated criticism from residents along the route, who say it will destroy their homes and countryside, and from many in the rail industry, who claim it will damage existing services while failing to achieve its stated objectives.

HS2 will not run to the main railway station in five of the seven major provincial cities it is due to serve, meaning that it will not connect properly to most local transport networks.